canfield



` nitrh @anni @fitta Letters Patent No. 82,799,'dated October 6, 1868.

IMPROVBD HOISTING-APPARATUS.

, @te .tlnhule etant tu iniflgese finitas ttent ma netting met nf tigesame.

TO ALL WHOM IT MAY CONCERN:

Be it known that I, F. I. C ANFILD, of Brighton, in 'the county ofMiddlesex, and State of Massachusetts, have invented certain new anduseful Improvements in HoistingApparatus and VI do hereby declare thatthe following is a full and exact description thereof, reference beinghad to the accompanying drawings, and to the letters of reference markedthereon. n

To enable others skilled in the art to make and use my invention, I willproceed to describe its nature, construction, and operation.

The nature of my invention consists- First, in suspending therope-barrel of a hoisting-apparatus upon levers, said levers being soarranged, 1n

combination with a friction-brake device, that the weight on thehoisting-barrel shall, acting through said levers and brake-device,cause suicient friction on the brake-wheel to hold it, so that themachine will always hold the suspended weight.

Second, in combining, with the abovemnentioned brake-device, levers, soconnected with the pull-rope, that, when sutlcient power is exerted onsaid pull-rope to lift the weight, the friction will be taken from thebrakewheel.

Drawings.

Figure 1 is a perspective view.

Figure 2 is a vertical section.

A B represent a frame, to which all parts of the machine are attached.

C is the rope or Winding-barrel, revolving cna journal, H. The journalsH, at cach end of the windingbarrel, run in boxes, which rest uponlevers L L', but are supported laterally by the housing K'. The ends ofthc levers L L' rest upon short Aarms M' M', projecting from the shaftM. This shaft M has also an arm, I, to which one end of the Abrake-strapa b c, fig. 2, is made fast, the other 'end of the str-apbeing attachedto thc' frame of the machine, as shown at d, iig. 2. As thebrakestr-:iprpasses over the brake-wheel, it will be seen that anypressure brought upou the levers L L' will act, through' the arms M' M'and P, upon the brake-strap a I; c, and thus cause friction upon thebrake-wheel E. y

Since the journals of the winding-barrel C rest upon the levers L L', itis obvious that the greaterthe weight upon C', the greater will be thefriction exertedy upon the brake-wheel.

The winding-barrel C is driven by the pinion D', which meshes into thespur-gear I), the pinion D' being driven by a rope-wheel, I",constructed in the usual manner. l

I will now proceed to describe the second part of my invention, that is,the device for removing thc friction on thc brake-wheel E.

Q Q' are parallel levers, one of which, Q, is attached to the shaft M,and, through the shaft M, serves to operate :he arm P, and thus to a`ctupon the brakestrap a b e. The lever Q ishuug to the frame of themachine.

R is a parallel bar, carrying two groored pulleys, S S'. Between thesepulleys the pull-rope T passes. When there is no tension upon thepull-rope, the levers Q Q will assume the vertical position,` and allowthe Wholeweight on the barrel C to rest upon the 'levers L L', and thusto act on the brake; but when force is exerted upon the pull-rope T, itwill-straighten, as represented by t t, and cause the levers Q Q' toassume the position represented by 1 7, lig. 2, which action throws upthe arm P, and loosens the brake-strap a Iz c, thus freeing thebrake-wheel from all friction.

X is a rope, attached to the lever Q, for the purpose of relieving thebrake-wheel of friction when it is desired to have the load lowered. f I

Various forms of mechanism might be employed, any one of which wouldeffect a transfer of a portion of the weight from the barrel to the braledevice, for the purposes of this apparatus. I have contemplated severalmodifications, among them, an inclined plane, as a'substitute for thelevers L L', for that -purpose. The

specific mode of eifeotingthis transfer is not the essence of myinvention, and therefore I do not limit myself to the particular devicedescribed for accomplishing that object.

I am aware that a number of hoisting-machines have been made, in whichthe weight, acting, not through the barrel and its journals, but throughreturn-rope, 35o., actuates some brake-device. I therefore limit myclaim tothe us'e of the' weight on th'e journals of' the winding-barrelYfor this purpose.

Claims.

What I claim as my invention, and desire to secure by Letters Patent of\the United States, is- 1. The hoisting-barrel C, when supportedindependently of the xed bearings K K', arranged and operatingsubstantially as shown, und for the purpose set forth.

2. The levers L'L, when so arranged, in relation to the winding-barrelC, as to convey a portion f tho weight suspended therefrom to act uponthe brake-device, substantially as described, andfor the purpose setforth.

3. The general arrangement ofv the levers Q Q', bar R, and guide-rollersSYS', when acted upon bythe A lateral motion of the pull-rope T,substantially as described, and for the purpose set forth.

Y n P. CANFIELD.

Witnesses:

WILLIAM Epsom FRANK G. PARKER.

